--- a/content/xml/content/src/nsXMLProcessingInstruction.h
+++ b/content/xml/content/src/nsXMLProcessingInstruction.h
@@ -80,12 +80,12 @@ protected:
    * which is used to parse the content of the PI.
    *
    * @param aName the name of the attribute to get the value for
    * @param aValue [out] the value for the attribute with name specified in
    *                     aAttribute. Empty if the attribute isn't present.
    */
   PRBool GetAttrValue(nsIAtom *aName, nsAString& aValue);
 
-  nsAutoString mTarget;
+  nsString mTarget;
 };
 
 #endif //nsIXMLProcessingInstruction_h___

--- a/docshell/base/nsDefaultURIFixup.h
+++ b/docshell/base/nsDefaultURIFixup.h
@@ -67,12 +67,12 @@ private:
     PRBool PossiblyByteExpandedFileName(const nsAString& aIn);
     PRBool PossiblyHostPortUrl(const nsACString& aUrl);
     PRBool MakeAlternateURI(nsIURI *aURI);
     PRBool IsLikelyFTP(const nsCString& aHostSpec);
     const char * GetFileSystemCharset();
     const char * GetCharsetForUrlBar();
 
     nsCOMPtr<nsIPrefBranch> mPrefBranch;
-    nsCAutoString mFsCharset;
+    nsCString mFsCharset;
 };
 
 #endif

--- a/dom/src/base/nsJSTimeoutHandler.cpp
+++ b/dom/src/base/nsJSTimeoutHandler.cpp
@@ -94,17 +94,17 @@ public:
   void ReleaseJSObjects();
 
 private:
 
   nsCOMPtr<nsIScriptContext> mContext;
 
   // filename, line number and JS language version string of the
   // caller of setTimeout()
-  nsCAutoString mFileName;
+  nsCString mFileName;
   PRUint32 mLineNo;
   PRUint32 mVersion;
   nsCOMPtr<nsIArray> mArgv;
 
   // The JS expression to evaluate or function to call, if !mExpr
   JSString *mExpr;
   JSObject *mFunObj;
 };

--- a/dom/src/storage/nsDOMStorage.h
+++ b/dom/src/storage/nsDOMStorage.h
@@ -186,17 +186,17 @@ protected:
 
   // true if items from the database are cached
   PRPackedBool mItemsCached;
 
   // the URI this store is associated with
   nsCOMPtr<nsIURI> mURI;
 
   // domain this store is associated with
-  nsAutoString mDomain;
+  nsString mDomain;
 
   // the key->value item pairs
   nsTHashtable<nsSessionStorageEntry> mItems;
 
 #ifdef MOZ_STORAGE
   static nsDOMStorageDB* gStorageDB;
 #endif
 };